A 0.5-ampere current is flowing through a long electrically conducting cylindrical rod. The diameter of the rod is 6 mm, the electrical resistance of the rod is R = 2000 Vm. and k-0.9 W/m K for the rod. The rod is encased in a 2-mm thick Pyrex tube and a 20°C liquid is flowing over the outer surface of the Pyrex tube. The convection heat transfer coefficient for the liquid h= 800 W/m2 K. The interfacial conductance (contact resistance) at the interface between the rod and the Pyrex tube is h = 1200 W/m² - K. a) Compute the rate of heat generation in the rod and use it compute the volumetric rate of heat generation. b) Find the temperature drop across the interface between the outer surface of the rod and the inner surface of the Pyrex tube. c) Find the temperature at the center of the rod.

A 0.5-ampere current is flowing through a long electrically conducting cylindrical rod. The diameter of the rod is 6 mm, the electrical resistance of the rod is R = 2000 Vm. and k-0.9 W/m K for the rod. The rod is encased in a 2-mm thick Pyrex tube and a 20°C liquid is flowing over the outer surface of the Pyrex tube. The convection heat transfer coefficient for the liquid h= 800 W/m2 K. The interfacial conductance (contact resistance) at the interface between the rod and the Pyrex tube is h = 1200 W/m² - K. a) Compute the rate of heat generation in the rod and use it compute the volumetric rate of heat generation. b) Find the temperature drop across the interface between the outer surface of the rod and the inner surface of the Pyrex tube. c) Find the temperature at the center of the rod.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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Question

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A 0.5-ampere current is flowing through a long electrically conducting cylindrical rod.
The diameter of the rod is 6 mm, the electrical resistance of the rod is R = 2000 /m,
and k =0.9 W/m K for the rod. The rod is encased in a 2-mm thick Pyrex tube and a
20°C liquid is flowing over the outer surface of the Pyrex tube. The convection heat
transfer coefficient for the liquid h= 800 W/m2 . K. The interfacial conductance (contact
resistance) at the interface between the rod and the Pyrex tube is h = 1200 W/m² - K.
a) Compute the rate of heat generation in the rod and use it compute the volumetric
rate of heat generation.
b) Find the temperature drop across the interface between the outer surface of the rod
and the inner surface of the Pyrex tube.
c) Find the temperature at the center of the rod.

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